Unit Rate
Josh drives 180 miles in 3 hours. What is his speed in miles per hour
INCLUDE UNITS in your answer
60 mph (miles per hour)
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180miles / 3 hours = 60 mph
Find a ratio that is equivalent to 5:10.
Answers vary
Apples are on sale for $3.12 per pound.
Make a table with three ratios that shows this relationship
Answers vary
How do you find the CONSTANT OF PROPORTIONALITY?
y / x or the value of y when x = 1
Does this graph show a proportional relationship?
Yes!
Celia paid $12 for a bag of 3 goldfish. What was the cost of 1 goldfish?
$4
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$12 / 3 goldfish = $4 per goldfish
Are the ratios 3:4 and 10:12 equivalent?
No
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4 / 3 = 1.33333333
12 / 10 = 1.2
Miss Perkins went to Target and saw that she could buy one pair of shoes for $29.99 or two pairs of shoes for $59.98. Make a table for these ratios and determine if they are proportional.
See the screen
Find the constant of proportionality for these ratios
10
Does this graph show a proportional relationship?
No
If you went to DQ and paid $4.80 for 12 ounces of fro-yo, what does DQ charge for each ounce of fro-yo?
$0.40 per ounce
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$4.80 / 12 ounces = $0.40 per ounce
Which graph shows a proportional relationship and how do you know?
Graph D because it is the only linear relationship that also includes the point (0, 0)
Make a table for ALL the points in the graph on the screen
See the screen
Find the constant of proportionality in the graph
46
What are the two requirements that graphs have if they show a proportional relationship?
1. The points appear in a straight line
2. The line goes through the origin
Sydney read 30 pages in 90 minutes. She reads at a constant rate.
How many pages can Sydney read per minute?
INCLUDE UNITS
1/3 page per minute
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30 pages / 90 minutes = 1/3 page per minute
Find the missing ratios in the ratio table
10, 35
Adrian's savings account started (Week 0) was $28. Each week, he deposits another $15 into that account, and he doesn't spend any of his savings.
Make a table for Weeks 1-4 to show Adrian's savings. Is the relationship proportional?
Check the screen for a correct answer
Find the constant of proportionality between candy and price.
0.05
Draw a graph that is proportional. Be prepared to explain what makes it proportional.
Miss Perkins is at Costco and wants to buy ice cream. There is a 18 ounce tub for $4.99 or a 24 ounce tub for $7.85.
Which is the better buy? Show work to support your choice.
The smaller tub is a better buy because it costs $0.28 per ounce, while the other one costs $0.33 per ounce.
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$4.99 / 18 = 0.2772 = $0.28 per ounce
$7.85 / 24 = 0.327 = $0.33 per ounce
Miss Perkins signed up for a promotion that got her three free sandwiches from Jimmy Johns. After that, she had to pay the regular cost of $6.99 per sandwich.
Is the number of sandwiches bought proportional to the total cost? Why or why not?
No, Miss Perkins did not pay the same amount for each sandwich.
Find three ratios that are equivalent to 18:4.
Answer vary
What is the constant of proportionality for this table?
There is not a constant of proportionality because 4/1 = 4 and 1/4 = 0.25
Draw a graph of a relationship that is not proportional. Be prepared to tell what makes it not proportional.
Show that graph!